Five-membered ring formation in unimolecular reactions of peptides: a key structural element controlling low-energy collision-induced dissociation of peptides

✍ Scribed by Andreas Schlosser; Wolf D. Lehmann

• Publisher: John Wiley and Sons
• Year: 2000
• Tongue: English
• Weight: 135 KB
• Volume: 35
• Category: Article
• ISSN: 1076-5174
• DOI: 10.1002/1096-9888(200012)35:12<1382::aid-jms84>3.0.co;2-6

✦ Synopsis

Unimolecular fragmentation reactions of peptides in low-energy collision-induced dissociation are reviewed in the mechanistic context of five-membered ring formation. This structure of intermediates or of fragment ions is recognized as a key element that governs unimolecular peptide fragmentation within the structural framework determined by the peptide backbone and its side-chains. A collection of collision-induced dissociation reactions is presented covering (i) b-ion formation, (ii) the fragmentation of N-terminally acylated peptides, (iii) neutral loss of the C-terminal amino acid in alkali or silver cationized peptides, (iv) the fragmentation of isoAsp-containing peptides and (v) the fragmentation of negatively charged Asp- or Glu-containing peptides. It appears that for all possible nucleophile-electrophile interactions leading to a five-membered ring structure an associated unimolecular peptide fragmentation reaction can be observed.